source4/auth/gensec/schannel.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    dcerpc schannel operations
   5
   6    Copyright (C) Andrew Tridgell 2004
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "librpc/gen_ndr/ndr_schannel.h"
  25 #include "auth/auth.h"
  26 #include "auth/credentials/credentials.h"
  27 #include "auth/gensec/gensec.h"
  28 #include "auth/gensec/gensec_internal.h"
  29 #include "auth/gensec/gensec_proto.h"
  30 #include "../libcli/auth/schannel.h"
  31 #include "librpc/gen_ndr/dcerpc.h"
  32 #include "param/param.h"
  33 #include "auth/gensec/gensec_toplevel_proto.h"
  34
  35 _PUBLIC_ NTSTATUS gensec_schannel_init(void);
  36
  37 static size_t schannel_sig_size(struct gensec_security *gensec_security, size_t data_size)
  38 {
  39         struct schannel_state *state =
  40                 talloc_get_type_abort(gensec_security->private_data,
  41                 struct schannel_state);
  42
  43         return netsec_outgoing_sig_size(state);
  44 }
  45
  46 static NTSTATUS schannel_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx,
  47                                 struct tevent_context *ev,
  48                                 const DATA_BLOB in, DATA_BLOB *out)
  49 {
  50         struct schannel_state *state =
  51                 talloc_get_type(gensec_security->private_data,
  52                 struct schannel_state);
  53         NTSTATUS status;
  54         enum ndr_err_code ndr_err;
  55         struct NL_AUTH_MESSAGE bind_schannel;
  56         struct NL_AUTH_MESSAGE bind_schannel_ack;
  57         struct netlogon_creds_CredentialState *creds;
  58         const char *workstation;
  59         const char *domain;
  60
  61         *out = data_blob(NULL, 0);
  62
  63         switch (gensec_security->gensec_role) {
  64         case GENSEC_CLIENT:
  65                 if (state != NULL) {
  66                         /* we could parse the bind ack, but we don't know what it is yet */
  67                         return NT_STATUS_OK;
  68                 }
  69
  70                 creds = cli_credentials_get_netlogon_creds(gensec_security->credentials);
  71                 if (creds == NULL) {
  72                         return NT_STATUS_INVALID_PARAMETER_MIX;
  73                 }
  74
  75                 state = netsec_create_state(gensec_security,
  76                                             creds, true /* initiator */);
  77                 if (state == NULL) {
  78                         return NT_STATUS_NO_MEMORY;
  79                 }
  80                 gensec_security->private_data = state;
  81
  82                 bind_schannel.MessageType = NL_NEGOTIATE_REQUEST;
  83 #if 0
  84                 /* to support this we'd need to have access to the full domain name */
  85                 /* 0x17, 23 */
  86                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
  87                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME |
  88                                       NL_FLAG_UTF8_DNS_DOMAIN_NAME |
  89                                       NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME;
  90                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
  91                 bind_schannel.oem_netbios_computer.a = creds->computer_name;
  92                 bind_schannel.utf8_dns_domain = cli_credentials_get_realm(gensec_security->credentials);
  93                 /* w2k3 refuses us if we use the full DNS workstation?
  94                  why? perhaps because we don't fill in the dNSHostName
  95                  attribute in the machine account? */
  96                 bind_schannel.utf8_netbios_computer = creds->computer_name;
  97 #else
  98                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
  99                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME;
 100                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
 101                 bind_schannel.oem_netbios_computer.a = creds->computer_name;
 102 #endif
 103
 104                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel,
 105                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 106                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 107                         status = ndr_map_error2ntstatus(ndr_err);
 108                         DEBUG(3, ("Could not create schannel bind: %s\n",
 109                                   nt_errstr(status)));
 110                         return status;
 111                 }
 112
 113                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 114         case GENSEC_SERVER:
 115
 116                 if (state != NULL) {
 117                         /* no third leg on this protocol */
 118                         return NT_STATUS_INVALID_PARAMETER;
 119                 }
 120
 121                 /* parse the schannel startup blob */
 122                 ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel,
 123                         (ndr_pull_flags_fn_t)ndr_pull_NL_AUTH_MESSAGE);
 124                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 125                         status = ndr_map_error2ntstatus(ndr_err);
 126                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 127                                   nt_errstr(status)));
 128                         return status;
 129                 }
 130
 131                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_DOMAIN_NAME) {
 132                         domain = bind_schannel.oem_netbios_domain.a;
 133                         if (strcasecmp_m(domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)) != 0) {
 134                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 135                                           domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)));
 136                                 return NT_STATUS_LOGON_FAILURE;
 137                         }
 138                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_DNS_DOMAIN_NAME) {
 139                         domain = bind_schannel.utf8_dns_domain.u;
 140                         if (strcasecmp_m(domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)) != 0) {
 141                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 142                                           domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)));
 143                                 return NT_STATUS_LOGON_FAILURE;
 144                         }
 145                 } else {
 146                         DEBUG(3, ("Request for schannel to without domain\n"));
 147                         return NT_STATUS_LOGON_FAILURE;
 148                 }
 149
 150                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_COMPUTER_NAME) {
 151                         workstation = bind_schannel.oem_netbios_computer.a;
 152                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME) {
 153                         workstation = bind_schannel.utf8_netbios_computer.u;
 154                 } else {
 155                         DEBUG(3, ("Request for schannel to without netbios workstation\n"));
 156                         return NT_STATUS_LOGON_FAILURE;
 157                 }
 158
 159                 status = schannel_get_creds_state(out_mem_ctx,
 160                                                   gensec_security->settings->lp_ctx,
 161                                                   workstation, &creds);
 162                 if (!NT_STATUS_IS_OK(status)) {
 163                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 164                                   workstation, nt_errstr(status)));
 165                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 166                                 return NT_STATUS_LOGON_FAILURE;
 167                         }
 168                         return status;
 169                 }
 170
 171                 state = netsec_create_state(gensec_security,
 172                                             creds, false /* not initiator */);
 173                 if (state == NULL) {
 174                         return NT_STATUS_NO_MEMORY;
 175                 }
 176                 gensec_security->private_data = state;
 177
 178                 bind_schannel_ack.MessageType = NL_NEGOTIATE_RESPONSE;
 179                 bind_schannel_ack.Flags = 0;
 180                 bind_schannel_ack.Buffer.dummy = 0x6c0000; /* actually I think
 181                                                             * this does not have
 182                                                             * any meaning here
 183                                                             * - gd */
 184
 185                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack,
 186                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 187                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 188                         status = ndr_map_error2ntstatus(ndr_err);
 189                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 190                                   workstation, nt_errstr(status)));
 191                         return status;
 192                 }
 193
 194                 return NT_STATUS_OK;
 195         }
 196         return NT_STATUS_INVALID_PARAMETER;
 197 }
 198
 199 /**
 200  * Returns anonymous credentials for schannel, matching Win2k3.
 201  *
 202  */
 203
 204 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 205                                       TALLOC_CTX *mem_ctx,
 206                                       struct auth_session_info **_session_info)
 207 {
 208         return auth_anonymous_session_info(mem_ctx, gensec_security->settings->lp_ctx, _session_info);
 209 }
 210
 211 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 212 {
 213         return NT_STATUS_OK;
 214 }
 215
 216 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 217 {
 218         return NT_STATUS_OK;
 219 }
 220
 221 static bool schannel_have_feature(struct gensec_security *gensec_security,
 222                                          uint32_t feature)
 223 {
 224         if (feature & (GENSEC_FEATURE_SIGN |
 225                        GENSEC_FEATURE_SEAL)) {
 226                 return true;
 227         }
 228         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 229                 return true;
 230         }
 231         return false;
 232 }
 233
 234 /*
 235   unseal a packet
 236 */
 237 static NTSTATUS schannel_unseal_packet(struct gensec_security *gensec_security,
 238                                        uint8_t *data, size_t length,
 239                                        const uint8_t *whole_pdu, size_t pdu_length,
 240                                        const DATA_BLOB *sig)
 241 {
 242         struct schannel_state *state =
 243                 talloc_get_type_abort(gensec_security->private_data,
 244                 struct schannel_state);
 245
 246         return netsec_incoming_packet(state, true,
 247                                       discard_const_p(uint8_t, data),
 248                                       length, sig);
 249 }
 250
 251 /*
 252   check the signature on a packet
 253 */
 254 static NTSTATUS schannel_check_packet(struct gensec_security *gensec_security,
 255                                       const uint8_t *data, size_t length,
 256                                       const uint8_t *whole_pdu, size_t pdu_length,
 257                                       const DATA_BLOB *sig)
 258 {
 259         struct schannel_state *state =
 260                 talloc_get_type_abort(gensec_security->private_data,
 261                 struct schannel_state);
 262
 263         return netsec_incoming_packet(state, false,
 264                                       discard_const_p(uint8_t, data),
 265                                       length, sig);
 266 }
 267 /*
 268   seal a packet
 269 */
 270 static NTSTATUS schannel_seal_packet(struct gensec_security *gensec_security,
 271                                      TALLOC_CTX *mem_ctx,
 272                                      uint8_t *data, size_t length,
 273                                      const uint8_t *whole_pdu, size_t pdu_length,
 274                                      DATA_BLOB *sig)
 275 {
 276         struct schannel_state *state =
 277                 talloc_get_type_abort(gensec_security->private_data,
 278                 struct schannel_state);
 279
 280         return netsec_outgoing_packet(state, mem_ctx, true,
 281                                       data, length, sig);
 282 }
 283
 284 /*
 285   sign a packet
 286 */
 287 static NTSTATUS schannel_sign_packet(struct gensec_security *gensec_security,
 288                                      TALLOC_CTX *mem_ctx,
 289                                      const uint8_t *data, size_t length,
 290                                      const uint8_t *whole_pdu, size_t pdu_length,
 291                                      DATA_BLOB *sig)
 292 {
 293         struct schannel_state *state =
 294                 talloc_get_type_abort(gensec_security->private_data,
 295                 struct schannel_state);
 296
 297         return netsec_outgoing_packet(state, mem_ctx, false,
 298                                       discard_const_p(uint8_t, data),
 299                                       length, sig);
 300 }
 301
 302 static const struct gensec_security_ops gensec_schannel_security_ops = {
 303         .name           = "schannel",
 304         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 305         .client_start   = schannel_client_start,
 306         .server_start   = schannel_server_start,
 307         .update         = schannel_update,
 308         .seal_packet    = schannel_seal_packet,
 309         .sign_packet    = schannel_sign_packet,
 310         .check_packet   = schannel_check_packet,
 311         .unseal_packet  = schannel_unseal_packet,
 312         .session_info   = schannel_session_info,
 313         .sig_size       = schannel_sig_size,
 314         .have_feature   = schannel_have_feature,
 315         .enabled        = true,
 316         .priority       = GENSEC_SCHANNEL
 317 };
 318
 319 _PUBLIC_ NTSTATUS gensec_schannel_init(void)
 320 {
 321         NTSTATUS ret;
 322         ret = gensec_register(&gensec_schannel_security_ops);
 323         if (!NT_STATUS_IS_OK(ret)) {
 324                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 325                         gensec_schannel_security_ops.name));
 326                 return ret;
 327         }
 328
 329         return ret;
 330 }